In a portable telephone, there is used a light emitting diode (hereinafter referred to as LED) for decoration and notification. LEDs are also used for a display device of the portable telephone.
It is preferred that the display device using LEDs has high light emission quality. For example, there is proposed a structure for improving the light emission quality of backlight in a liquid crystal display device (see Patent Document 1).
Patent Document 1: Japanese Patent Laid Open Publication No. 2004-079488 (paragraph 0020, FIG. 10)